The overall goal of this Mentored Patient-Oriented Research Career Development Award (K23) is to support the applicant in developing the skills to launch an independent research program focused on implementing evidence-based mental health treatments/practices (EBP) in the juvenile justice system. Specific training goals are: (1) expertise in conducting dissemination and implementation (D&I) research in juvenile justice settings and (2) mixed methods analytic approaches for D&I research. The applicant will pursue these goals through a combination of mentoring, didactics, and practical experience. Key mentors include Drs. Kimberly Hoagwood (New York University), Mary McKay (Mount Sinai School of Medicine/NYU), and Julian Ford (University of Connecticut). The objective of the proposed research plan is to pilot-test an innovative multi-phase Technical Assistance and Implementation Support (TAIS) model designed to promote the adoption of an evidence-based intervention for traumatic stress (PTSD) in juvenile justice agencies. PTSD is one of the more prevalent and impairing disorders among justice-involved youth yet proven treatments are not widely available in this system or the community mental health systems where youth offenders are referred. Factors that limit the availability of EBP in JJ include the lack of proven strategie for implementing EBP in service settings, the limited number of clinicians in this system, and agency cultures/structures that are not receptive to new practices. The research plan is divided into 2 studies that build upon each other to address these gaps. Phase 1 of the TAIS model aims to increase agency readiness to adopt EBP while Phase 2 consists of consultation on implementing an EBP. The primary aims are: (1) evaluate the impact of an organizational intervention on agency readiness for EBP (Phase 1) using an interrupted time series design (n=4 agencies); use mixed methods to examine contextual factors that influence agency outcomes; and examine the impact of a consultation model on staff mastery/adoption of a PTSD group intervention. In a novel twist, front-line juvenile justice staff (i.e., non-clinicians) will undergo training to deliver EBP. A hybrid implementation/effectiveness design will be used to concurrently assess the impact of the EBP consultation model and of EBP delivered by non-clinicians. To assess the latter, 48-64 youth offenders will be randomized to 10-weeks of EBP groups led by justice staff or treatment as usual (referral to community provider). It is hypothesized that the TAIS model will significantly increase agency readiness for EBP, which will lead to improved EBP implementation outcomes. EBP groups delivered by justice staff are expected to produce superior youth outcomes (PTSD, delinquency) to TAU. Findings will be used to refine the TAIS model in preparation for a R01 trial. Completion of this project will: (1) advance knowledge on effective strategies to promote sustained EBP uptake in practice settings; (2) provide pilot data for a R01 for a larger- scale test of the TAIS model; and (3) provide the applicant with the mentored training and protected time needed to launch an independent research career.